1/*
2 * Driver for the SH-Mobile MIPI CSI-2 unit
3 *
4 * Copyright (C) 2010, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <linux/delay.h>
12#include <linux/err.h>
13#include <linux/i2c.h>
14#include <linux/io.h>
15#include <linux/platform_device.h>
16#include <linux/pm_runtime.h>
17#include <linux/slab.h>
18#include <linux/videodev2.h>
19#include <linux/module.h>
20
21#include <media/sh_mobile_ceu.h>
22#include <media/sh_mobile_csi2.h>
23#include <media/soc_camera.h>
24#include <media/soc_mediabus.h>
25#include <media/v4l2-common.h>
26#include <media/v4l2-dev.h>
27#include <media/v4l2-device.h>
28#include <media/v4l2-mediabus.h>
29#include <media/v4l2-subdev.h>
30
31#define SH_CSI2_TREF	0x00
32#define SH_CSI2_SRST	0x04
33#define SH_CSI2_PHYCNT	0x08
34#define SH_CSI2_CHKSUM	0x0C
35#define SH_CSI2_VCDT	0x10
36
37struct sh_csi2 {
38	struct v4l2_subdev		subdev;
39	unsigned int			irq;
40	unsigned long			mipi_flags;
41	void __iomem			*base;
42	struct platform_device		*pdev;
43	struct sh_csi2_client_config	*client;
44};
45
46static void sh_csi2_hwinit(struct sh_csi2 *priv);
47
48static int sh_csi2_try_fmt(struct v4l2_subdev *sd,
49			   struct v4l2_mbus_framefmt *mf)
50{
51	struct sh_csi2 *priv = container_of(sd, struct sh_csi2, subdev);
52	struct sh_csi2_pdata *pdata = priv->pdev->dev.platform_data;
53
54	if (mf->width > 8188)
55		mf->width = 8188;
56	else if (mf->width & 1)
57		mf->width &= ~1;
58
59	switch (pdata->type) {
60	case SH_CSI2C:
61		switch (mf->code) {
62		case MEDIA_BUS_FMT_UYVY8_2X8:		/* YUV422 */
63		case MEDIA_BUS_FMT_YUYV8_1_5X8:		/* YUV420 */
64		case MEDIA_BUS_FMT_Y8_1X8:		/* RAW8 */
65		case MEDIA_BUS_FMT_SBGGR8_1X8:
66		case MEDIA_BUS_FMT_SGRBG8_1X8:
67			break;
68		default:
69			/* All MIPI CSI-2 devices must support one of primary formats */
70			mf->code = MEDIA_BUS_FMT_YUYV8_2X8;
71		}
72		break;
73	case SH_CSI2I:
74		switch (mf->code) {
75		case MEDIA_BUS_FMT_Y8_1X8:		/* RAW8 */
76		case MEDIA_BUS_FMT_SBGGR8_1X8:
77		case MEDIA_BUS_FMT_SGRBG8_1X8:
78		case MEDIA_BUS_FMT_SBGGR10_1X10:	/* RAW10 */
79		case MEDIA_BUS_FMT_SBGGR12_1X12:	/* RAW12 */
80			break;
81		default:
82			/* All MIPI CSI-2 devices must support one of primary formats */
83			mf->code = MEDIA_BUS_FMT_SBGGR8_1X8;
84		}
85		break;
86	}
87
88	return 0;
89}
90
91/*
92 * We have done our best in try_fmt to try and tell the sensor, which formats
93 * we support. If now the configuration is unsuitable for us we can only
94 * error out.
95 */
96static int sh_csi2_s_fmt(struct v4l2_subdev *sd,
97			 struct v4l2_mbus_framefmt *mf)
98{
99	struct sh_csi2 *priv = container_of(sd, struct sh_csi2, subdev);
100	u32 tmp = (priv->client->channel & 3) << 8;
101
102	dev_dbg(sd->v4l2_dev->dev, "%s(%u)\n", __func__, mf->code);
103	if (mf->width > 8188 || mf->width & 1)
104		return -EINVAL;
105
106	switch (mf->code) {
107	case MEDIA_BUS_FMT_UYVY8_2X8:
108		tmp |= 0x1e;	/* YUV422 8 bit */
109		break;
110	case MEDIA_BUS_FMT_YUYV8_1_5X8:
111		tmp |= 0x18;	/* YUV420 8 bit */
112		break;
113	case MEDIA_BUS_FMT_RGB555_2X8_PADHI_BE:
114		tmp |= 0x21;	/* RGB555 */
115		break;
116	case MEDIA_BUS_FMT_RGB565_2X8_BE:
117		tmp |= 0x22;	/* RGB565 */
118		break;
119	case MEDIA_BUS_FMT_Y8_1X8:
120	case MEDIA_BUS_FMT_SBGGR8_1X8:
121	case MEDIA_BUS_FMT_SGRBG8_1X8:
122		tmp |= 0x2a;	/* RAW8 */
123		break;
124	default:
125		return -EINVAL;
126	}
127
128	iowrite32(tmp, priv->base + SH_CSI2_VCDT);
129
130	return 0;
131}
132
133static int sh_csi2_g_mbus_config(struct v4l2_subdev *sd,
134				 struct v4l2_mbus_config *cfg)
135{
136	struct sh_csi2 *priv = container_of(sd, struct sh_csi2, subdev);
137
138	if (!priv->mipi_flags) {
139		struct soc_camera_device *icd = v4l2_get_subdev_hostdata(sd);
140		struct v4l2_subdev *client_sd = soc_camera_to_subdev(icd);
141		struct sh_csi2_pdata *pdata = priv->pdev->dev.platform_data;
142		unsigned long common_flags, csi2_flags;
143		struct v4l2_mbus_config client_cfg = {.type = V4L2_MBUS_CSI2,};
144		int ret;
145
146		/* Check if we can support this camera */
147		csi2_flags = V4L2_MBUS_CSI2_CONTINUOUS_CLOCK |
148			V4L2_MBUS_CSI2_1_LANE;
149
150		switch (pdata->type) {
151		case SH_CSI2C:
152			if (priv->client->lanes != 1)
153				csi2_flags |= V4L2_MBUS_CSI2_2_LANE;
154			break;
155		case SH_CSI2I:
156			switch (priv->client->lanes) {
157			default:
158				csi2_flags |= V4L2_MBUS_CSI2_4_LANE;
159			case 3:
160				csi2_flags |= V4L2_MBUS_CSI2_3_LANE;
161			case 2:
162				csi2_flags |= V4L2_MBUS_CSI2_2_LANE;
163			}
164		}
165
166		ret = v4l2_subdev_call(client_sd, video, g_mbus_config, &client_cfg);
167		if (ret == -ENOIOCTLCMD)
168			common_flags = csi2_flags;
169		else if (!ret)
170			common_flags = soc_mbus_config_compatible(&client_cfg,
171								  csi2_flags);
172		else
173			common_flags = 0;
174
175		if (!common_flags)
176			return -EINVAL;
177
178		/* All good: camera MIPI configuration supported */
179		priv->mipi_flags = common_flags;
180	}
181
182	if (cfg) {
183		cfg->flags = V4L2_MBUS_PCLK_SAMPLE_RISING |
184			V4L2_MBUS_HSYNC_ACTIVE_HIGH | V4L2_MBUS_VSYNC_ACTIVE_HIGH |
185			V4L2_MBUS_MASTER | V4L2_MBUS_DATA_ACTIVE_HIGH;
186		cfg->type = V4L2_MBUS_PARALLEL;
187	}
188
189	return 0;
190}
191
192static int sh_csi2_s_mbus_config(struct v4l2_subdev *sd,
193				 const struct v4l2_mbus_config *cfg)
194{
195	struct sh_csi2 *priv = container_of(sd, struct sh_csi2, subdev);
196	struct soc_camera_device *icd = v4l2_get_subdev_hostdata(sd);
197	struct v4l2_subdev *client_sd = soc_camera_to_subdev(icd);
198	struct v4l2_mbus_config client_cfg = {.type = V4L2_MBUS_CSI2,};
199	int ret = sh_csi2_g_mbus_config(sd, NULL);
200
201	if (ret < 0)
202		return ret;
203
204	pm_runtime_get_sync(&priv->pdev->dev);
205
206	sh_csi2_hwinit(priv);
207
208	client_cfg.flags = priv->mipi_flags;
209
210	return v4l2_subdev_call(client_sd, video, s_mbus_config, &client_cfg);
211}
212
213static struct v4l2_subdev_video_ops sh_csi2_subdev_video_ops = {
214	.s_mbus_fmt	= sh_csi2_s_fmt,
215	.try_mbus_fmt	= sh_csi2_try_fmt,
216	.g_mbus_config	= sh_csi2_g_mbus_config,
217	.s_mbus_config	= sh_csi2_s_mbus_config,
218};
219
220static void sh_csi2_hwinit(struct sh_csi2 *priv)
221{
222	struct sh_csi2_pdata *pdata = priv->pdev->dev.platform_data;
223	__u32 tmp = 0x10; /* Enable MIPI CSI clock lane */
224
225	/* Reflect registers immediately */
226	iowrite32(0x00000001, priv->base + SH_CSI2_TREF);
227	/* reset CSI2 harware */
228	iowrite32(0x00000001, priv->base + SH_CSI2_SRST);
229	udelay(5);
230	iowrite32(0x00000000, priv->base + SH_CSI2_SRST);
231
232	switch (pdata->type) {
233	case SH_CSI2C:
234		if (priv->client->lanes == 1)
235			tmp |= 1;
236		else
237			/* Default - both lanes */
238			tmp |= 3;
239		break;
240	case SH_CSI2I:
241		if (!priv->client->lanes || priv->client->lanes > 4)
242			/* Default - all 4 lanes */
243			tmp |= 0xf;
244		else
245			tmp |= (1 << priv->client->lanes) - 1;
246	}
247
248	if (priv->client->phy == SH_CSI2_PHY_MAIN)
249		tmp |= 0x8000;
250
251	iowrite32(tmp, priv->base + SH_CSI2_PHYCNT);
252
253	tmp = 0;
254	if (pdata->flags & SH_CSI2_ECC)
255		tmp |= 2;
256	if (pdata->flags & SH_CSI2_CRC)
257		tmp |= 1;
258	iowrite32(tmp, priv->base + SH_CSI2_CHKSUM);
259}
260
261static int sh_csi2_client_connect(struct sh_csi2 *priv)
262{
263	struct device *dev = v4l2_get_subdevdata(&priv->subdev);
264	struct sh_csi2_pdata *pdata = dev->platform_data;
265	struct soc_camera_device *icd = v4l2_get_subdev_hostdata(&priv->subdev);
266	int i;
267
268	if (priv->client)
269		return -EBUSY;
270
271	for (i = 0; i < pdata->num_clients; i++)
272		if ((pdata->clients[i].pdev &&
273		     &pdata->clients[i].pdev->dev == icd->pdev) ||
274		    (icd->control &&
275		     strcmp(pdata->clients[i].name, dev_name(icd->control))))
276			break;
277
278	dev_dbg(dev, "%s(%p): found #%d\n", __func__, dev, i);
279
280	if (i == pdata->num_clients)
281		return -ENODEV;
282
283	priv->client = pdata->clients + i;
284
285	return 0;
286}
287
288static void sh_csi2_client_disconnect(struct sh_csi2 *priv)
289{
290	if (!priv->client)
291		return;
292
293	priv->client = NULL;
294
295	pm_runtime_put(v4l2_get_subdevdata(&priv->subdev));
296}
297
298static int sh_csi2_s_power(struct v4l2_subdev *sd, int on)
299{
300	struct sh_csi2 *priv = container_of(sd, struct sh_csi2, subdev);
301
302	if (on)
303		return sh_csi2_client_connect(priv);
304
305	sh_csi2_client_disconnect(priv);
306	return 0;
307}
308
309static struct v4l2_subdev_core_ops sh_csi2_subdev_core_ops = {
310	.s_power	= sh_csi2_s_power,
311};
312
313static struct v4l2_subdev_ops sh_csi2_subdev_ops = {
314	.core	= &sh_csi2_subdev_core_ops,
315	.video	= &sh_csi2_subdev_video_ops,
316};
317
318static int sh_csi2_probe(struct platform_device *pdev)
319{
320	struct resource *res;
321	unsigned int irq;
322	int ret;
323	struct sh_csi2 *priv;
324	/* Platform data specify the PHY, lanes, ECC, CRC */
325	struct sh_csi2_pdata *pdata = pdev->dev.platform_data;
326
327	if (!pdata)
328		return -EINVAL;
329
330	priv = devm_kzalloc(&pdev->dev, sizeof(struct sh_csi2), GFP_KERNEL);
331	if (!priv)
332		return -ENOMEM;
333
334	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
335	/* Interrupt unused so far */
336	irq = platform_get_irq(pdev, 0);
337
338	if (!res || (int)irq <= 0) {
339		dev_err(&pdev->dev, "Not enough CSI2 platform resources.\n");
340		return -ENODEV;
341	}
342
343	/* TODO: Add support for CSI2I. Careful: different register layout! */
344	if (pdata->type != SH_CSI2C) {
345		dev_err(&pdev->dev, "Only CSI2C supported ATM.\n");
346		return -EINVAL;
347	}
348
349	priv->irq = irq;
350
351	priv->base = devm_ioremap_resource(&pdev->dev, res);
352	if (IS_ERR(priv->base))
353		return PTR_ERR(priv->base);
354
355	priv->pdev = pdev;
356	priv->subdev.owner = THIS_MODULE;
357	priv->subdev.dev = &pdev->dev;
358	platform_set_drvdata(pdev, &priv->subdev);
359
360	v4l2_subdev_init(&priv->subdev, &sh_csi2_subdev_ops);
361	v4l2_set_subdevdata(&priv->subdev, &pdev->dev);
362
363	snprintf(priv->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s.mipi-csi",
364		 dev_name(&pdev->dev));
365
366	ret = v4l2_async_register_subdev(&priv->subdev);
367	if (ret < 0)
368		return ret;
369
370	pm_runtime_enable(&pdev->dev);
371
372	dev_dbg(&pdev->dev, "CSI2 probed.\n");
373
374	return 0;
375}
376
377static int sh_csi2_remove(struct platform_device *pdev)
378{
379	struct v4l2_subdev *subdev = platform_get_drvdata(pdev);
380	struct sh_csi2 *priv = container_of(subdev, struct sh_csi2, subdev);
381
382	v4l2_async_unregister_subdev(&priv->subdev);
383	pm_runtime_disable(&pdev->dev);
384
385	return 0;
386}
387
388static struct platform_driver __refdata sh_csi2_pdrv = {
389	.remove	= sh_csi2_remove,
390	.probe	= sh_csi2_probe,
391	.driver	= {
392		.name	= "sh-mobile-csi2",
393	},
394};
395
396module_platform_driver(sh_csi2_pdrv);
397
398MODULE_DESCRIPTION("SH-Mobile MIPI CSI-2 driver");
399MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
400MODULE_LICENSE("GPL v2");
401MODULE_ALIAS("platform:sh-mobile-csi2");
402